joining us now, pete williams, who i should tell you, is in the same building i am in but is at another camera because he needs to be close to his desk phone. it truly is that kind of day in the news, pete. thank you very much for being here. >> you bet. >> what do we know about what authorities have been able to find from combing through the pictures and videos in the two days since the bombing? >> well, i think you've summarized it well. the holy grail for them was to see someone setting down a heavy backpack or duffel bag, a black nylon bag, that they believe this relatively heavy bomb was carried in. they think it weighed about 20 pounds, setting it down at the scene of one or the other of the bombings, and then getting away. they believe they have found a picture like that, first from the store surveillance camera that you noted, but they since have been able to triangulate that or get other views of it from other pictures and recordings that people who are in the area have sent them. people who have sent them pictures not knowing what exactly was to be found on them, so, they see